The present invention relates to an optical coupling device and a method of making such a device which can readily provide highly efficient optical coupling between an optical device and an optical fiber.
In a known optical coupling device, such as that disclosed in the specification of Japanese Patent Laid-Open No. 28392/1982, a through-hole is provided in a guide for an optical fiber in such a manner that its diameter is larger than the outer diameter of the optical fiber, and the optical fiber is inserted into the through-hole and fixed thereto so as to optically couple the optical fiber to an optical device.
In the above-described known optical coupling device, however, since the aperture of the through-hole is larger than the outer diameter of the optical fiber, the insertion of the optical fiber into the through-hole does not ensure accurate positioning of the optical fiber. Therefore, in the assembly process, after the optical fiber has been inserted into the through-hole provided in the guide, and has been fixed thereto, the optical axis of the optical fiber is aligned with the optical device by holding the guide by a micro manipulator, and the guide is then fixed to a case which contains the optical device.
In this known type of optical coupling device, if several optical devices are to be integrated to form an array, the optical axes of the optical fibers must be individually aligned with the corresponding optical devices. Further, space is needed to provide a guide for each optical fiber and conduct the alignment work. This inhibits any reduction in size of and integration of the optical coupling device. In addition, when these known optical coupling devices are assembled into an optical integrated module, it is very difficult to align the optical axis of each of the optical fibers within the small module.